Filter and method of making the same



Jan: 27, 1931.

s. WILTSE 1,790,036

FILTER AND METHOD OF MAKING THE SAME Filed July 30, 1928 2 Sheets-Sheet l gmamtoo jaw/re? 275a Jan. 27, 1931. s. WILTSE FILTER AND METHOD OF MAKING THE SAME Filed July so, 1928 ZShetS-Sheet 2 Patented Jan. 27, 1931 SUMNER wmrsx, or person, mm-

mrnn um union or mine rm; sum

Application ma July so, 1920. Serial No. 288,141.

This invention relates to filters for use in the separation of solid particles from liquids the principal'object being the provision of an efiicient filter economical to manufacture, and the method of forming the same.

Another object is to rovide a filter having a maximum effective ree face area of radiation.

Another object is to provide a filter of ribbon-like form including a relatively flat sheet metal casing enclosing afiltering ele- -ment.

- Another object is to rovide a filter comprising a casing and a filtering element, the filtering element being of ribbon-like for- .mation, and the casing formed of sheet metal bent over the same and confining the edges thereof.

- 'Another object is to provide a. filter of the type above described in which .the surface the casing is provided with outward- :ly' extending projections or ribs serving to increase the effective free face area of radiationof the. filter.

Another object is to provide a filter initialformed into a generally ribbon or stripllke shape and then bent or otherwise formed into a compact structure ermittingthe "circulation of a cooling medium about the same.

Another object is to provide a combined.

oil filter and cooler comprising a filtering ielement 'of ribbon' or strip-like formation -.-,wh1ch-is bent to bring various portions of :the exterior surface thereof into adjacent but spaced relationship with other portions of -.t e' exterior surface thereof.

A further object is to provide in combinationawith a motor vehicle and the engine thereof, a combined oil cooler and filter com- I prising afiltering element of strip-like formation connected with the lubricating system-of theengine, the filtering element beingbent in swiral or other formation with ;portions of t e exterior surface thereof in .adjacent but spaced relationship to other portions ofwthe exterior surface thereof zwli er'ebyto form it into a compact-structure .iwhi'ch will permit flow of air or fluid through the. same, such structure being positioned back of the cooling fan of the engine whereby the air put in motion b the fan will be forced over the exterior sur aces of the filtering element and thereby cool the oil passing through the filter.

The above'being among-the objects of thepresent invention, the same consists in certain features of construction, and combinai tions of parts to be hereinafter described with reference to the accompanyi g drawings, and then claimed, having the fbove and other objects in view.

' In the accompanying drawings which illustrate a suitable embodiment of the present invention, and in which like numerals refer to like parts throughout the several difierent views,

Fig. 1 is a more or less diagrammatic side elevation of the engine for a inotor vehicle, the cooling radiator bein shown in connection therewith, and a com ined oil filter and cooler mounted thereon.

Fig. 2 is a plan view of a portion of the sheet metal strip employed as a casin or housing for the filtering element, be ore bending.

. Fig. 3.is a sectional view taken on the line 3 3 of Fig. 2.

Fig. 4. is an enlarged sectional view of the filtering element.

5 is an enlarged sectional view through the lter showing the manner in which t e sheet strip shown in Figs. 2 and 3 is assembled about the filtering element shown in Fi 4. f

Fig. 6 is a partially broken view of the Fig. 6 is a artially broken edge view of the assembled fi ter before bending.

Fig. 7 is a plan view of the assembled filter before bending.

spira formation for the purpose of compactness, and provided with a supporting bracket. Fig. 9 is a partially sectioned side view .of the filter shown in Fig. 8, taken as on line 9-9 of Fi 8. I

Fig. 10 1s a plan view of a filter having a modified form of casin or housing.

Fig. 11 is a sectiona view taken on line Ill-11 of Fig. 10.

Fi 8 is an end view of the filter into 4 Fig. 12 is a sectional view taken on line 1212 of Fig. 10.

Fig. 13 is a plan view of a filter rovided witha different modification of t e housing or casing construction.

ig. 14 is an enlarged sectional view taken on line 14-14 of Fig. 13.

Fig. 15 is a perspective view ofanother modified form of casing or housing construction.

Fig. 16 is a side view showin the manner in which the filter may be forme into a spiral and placed within a shell or casing through whic a cooling liquid may be circulated, the shell being shown in section.

It. has become well-known in the motor vehicle industry that an efficient filter for the lubricating oil of the engine is desirable, if not necessary, in order to obtain maximum life of the engine." The present invention deals-with a filter applicablefor this, as well as other uses, and rovides a construction that is extremely e cient in operation and exceedingly economical to manufacture. It is obvious, of course, that the filter may likewise be used for separatin the solids from liquids in connection with evices other than internal combustion engines.

It has also been recognized that results of equal im rtance, as far as engine life is concerne maybe obtained by maintaining the lubricating oil below a definite maximum temperature, as well asfiltering the oil, but

heretofore, as far as I am aware, the constructions havebeensuch that they were not feasible for production of motor vehicles due to the relatively great cost of applying them to the same, and consequently them appearance has been limited to racing cars where the need of the cooling feature is of major im ortance.

ue to the construction of the filter in the present invention I am enabled to so form it so as to' rovide an oil cooler of extremely efficient esign which is amply able to maintain the lubricating oil below a maximum desirable temperature with consequent advantages resulting therefrom.

' In accordance with the present invention I show in Figs. 2 and 3 astrip of sheet metal upon which the preliminary forming operations have, been made in order to prepare it as a housing or casing for the filtering ele-' ment for my filter. j

As shown in these figures the stri of metal has been formed'to provide four ongitudinally extending fiat portions 25 two of which extend along the margins of the strip, and the other two of which are positioned midway between the margins and separated by a relatively shallow trough shaped depression 26 provided to facilitate bending of the strip during a later operation. That portion of the sheet between each edge of the marginal portion 25 and-the adjacent central portion 25 is ofiset from the plane of the portions 25 a slight amount as at 27, and in t e portions 27 are formed similarl extending inverted trough-shaped or bea -like rojections or ribs 28 which extend at an ang e to the length of the strip. A filtering element is formed as indicated in Fig. 4 and comprises a strip of wire screen 29 which may be of relatively open mesh and of a width sli htly less than half of the width of the strip rom which the housing or casing is formed. The wire screen strip 29 is enclosed by a sheet 30 of filtering material which may be of fabric, fine wire mesh, or other suitable material desi ed to prevent the passage of solids theret rou h at permitting the passage ofli uids.. e strip shown in Figs. 2 and 3 is t en bent at the depression 26 about the filterin element shown in Fig. 4 as indicated in 1 5, the marginal edges being brought to et er and crimped as at 31 or otherwise seafed against leakage, and the margins of the filtering element 2930 being clam d between opposed faces 25. The ends oft e housing or casin strip are spread as at 32 and 33 in ig. 6, an

the filtering element at one end is bent against terial 30 over the greater part of the widthof the filtering element so as to form chambers or passages 35 and 36 to permit the flow of liquid between the filtering element and-the portion 27 of the housing on either side of the ltering element.

In operation, oilor other liquid is introduced t rough one of the connections 34 and flows lengthwise of the filter through one of the chambers 35 or 36 between the ortion 27 and the adjacent fabric 30, and ue to the difference in pressure between the inlet and outlet of, the'filter, the ,oil or liquid passes through the fabric 30 and into thespace 35 or 36, as the case may be, between the opposite portion 27 and the adjacent fabric 30 where it is conducted to the discharge connection 34. In. ractice, I make the filter of relatively great ength so that a maximum area of the material 30 is presented for the passage of the liquid therethrough. This insures a minimum velocity of the liquid being filtered ig. 5 it will be noted that the with consequent efiiciency in-removal of the solids therefrom. The projections or ribs 28 are formedprimarily to increase the'efiective free face area of radiation of the housing so I that the housing in being heated by the oil or other liquid passing through the same will present a maximum free area of external radiation surface for dissipation of the heat' carried by the liquid. This feature enables the filter to be used not merely as a filter for .use in connection with the lubrication system of an internal combustion engine, but also as a means for cooling the lubricatin oil.

It will be obvious that the ribbonikefilter indicated in Figs. 6 and 7 may be employed in such form, that is, flat, to function both as a filter and an oil cooler and in fact where such construction is employed in connection with the engines of airplanes and the like where a. minimum air resistance is necessary,

it may be preferable to leave the filter in the flat condition. However, when such filter is employed in connection with a motor vehicle,

it is usually desirable that it be as compact as possible, and the construction of the present filter lends itself to this feature. This may be accomplished as indicated in Figs. 8 and 9 in which the filter iscoiled up to form a spiral formation, the various coils of which are slightly spaced from each other so as to form air pasasges 40 extending from one side to the other between the various coils. The filter thus coiled as indicated in Figs. 8 and 9 may be provided with a suitable supporting means such as the sheet metal strip 41 which is bent around the same and is clamped in such position by means of one or more bolts 42 extending between the opposite ends of the strip 41 and drawn into place by nuts such-as 4 3, the free ends of the strip being bent outwardly as at 44 to form attaching portions a tube such as 64 to the'discharge side of the oil pump 65 of the engine 46, and the other-connection 34 is connected to a tube such as 66 leading to .the various bearing surfaces (not shown) of the engine. This method of connecting up the .filter may, of course, be varied, such as by providing means whereby only a portion of the oil from the pump 65 passes through the'filter, as in some conventional constructions.

This assembly is preferably secured im-' mediately back of the fan 45 of .the engine 46 with its axis parallel to the axis of the fan so that when the fan is rotating to draw air through the radiator 47 such air is forced through the passages 40 and thereby absorbsheat from the filter. It will be noted that when the beads or projections 28 are formed at an angle to the length of the filter strips, as indicated in Fig. 2.,the air passages 40 between the various coils. of. the filter will impart to the air passed through the filter a swirling motionwhich will cause the air to come into more intimate contact with the radiating surfaces .of the filter and also maintain such air iii-contact with the surface of the filter for a greater length of time than if it were passed directly through the same, due to the fact that the travel path of. the

air through the filter is greater. Furthermore, when the beads or projections 28 are placed at an angle, as shown, the provide means whereby t e outer surfaceo each coil may stretch and the inner surface be compressed when the strip-like filter is being wound into the spiral.

It is, of course, not essential that the beads or ribs 28 be employed at all, or if employed, be disposed as indicated in Figs. 2 and 3. In fact, it may be found desirable to replace them with longitudinally extended beads or ribs such as indicated at 48 in Figs. 10, 11 and 12, and in which that portion 49 of the strip between the beads 48 bears against the fabric portion 30 of the filtering element. In this case, inasmuch as the beads or projections 48 extend longitudinally of the filter from end to end no chamber such as 35 and 36 need be specially provided, inasmuch as the areaenclosed by such beads or projections provides passages for the liquid being filtered "from one end of the filter to the other. Where such longitudinally extending beads or ribs 48 are employed and I desire to coil the filter as indicated in Figs. 8 and 9, I, prefer to provide transverse beads or ribs such as 50 at spaced intervals along the length of the filter so that in coiling up the filter the outer beads or ribs 50 may stretch and the inner ones be compressed to facilitate such coiling.

Instead of the beads or ribs as disclosed 'in the previous figures the surface of the portion 27 may be provided with a plurality of projections such as indicated at 55 in Figs. 13 and 14, the effect of the same being to increase the effective free area of radiation of the filter as in the previous cases. The construction may also be varied as indicated in Figs. 15 in which the filter is provided with transversely extending rib or bead portions 58. This last: construction permits great ease in coiling the filter element to the position shown in Figs. 8 and 9 and the space between the various ribs or beads 58.provide direct paths for the passage of air between the front and rear faces of the same.

It is to be noted that in the construction shown in Figs. 5.and l4 chambers 35 and 36 are-provided on each side of the fabric 30. This may not at all be essential, particularly where the sheet metal housing or casing for the fabric 30 is formed"v of very thin sheet metal as is preferable both' from the standtend to separate the side portions 27 of the filter and will thereby provide sufficient area portion of the filter may govern, in. some cases, the articular manner of coiling or otherwise forming the same 1nto a compact structure. For instance, in the construction shown in Figs. 6 and 7 some of the ribs of one coil may contact with some of the ribs of the adjacent coil when formed as in Figs. 8 and 9, the spaces between the ribs forming air ducts for the passa e of air from the front to the rear face of t e assembly. However, where ribs such as 48 in Figs. 10, 11 and 12 are employed, the ribs 48 of one coil should not contact with the ribs 48 of thenext coil or such 'air passage through the filter would be prevente In any case, the various coils should be in generally spaced relation with respect to each other, as shown, to ermit the flow of air between them, as will readily ap arent. y

11 some constructions it may be desirable to cool the filter by a coolingliquid rather than air, and in such case it is obvious that the filter coiled as shown in Figs. 8 and 9 maybe inserted in a shell such as 60 in Fig. 16, such shell being provided with a liquid inlet such as 61 and liquid outlet such as 62.

.relatively thin elongated sheet metal hous- The shell 60 in such case preferably contacts with the outer surface of the coiled filter as indicated in Fig. 16, and the inlet 61 is positioned on the opposite side of the filter from the outlet 62 thus insuring all of the cooling li uid enterin the inlet 61 passing through t e coils of t e filter before escaping through the outlet 62.

It is to be further noted that although I have described the foregoing constructions as adaptable for cooling the filtered liquid, it is obvious that in some cases it may be desirable to emplo them for heating 'the filtered liquid, an as such constructions are primarily heat interchange devices, their application as heating means is obvious.

Anotherj-ffeature which is obvious, but

which may-well be noted, is that although I have described the above constructions as being primarily filters, the primary function of the same may well be that of a heat interchange device or radiator, and in fact where the filtering feature is of such minor importance as; to'be disregarded, the constructlons coiled as in Figs. 8 and 9 may be cmplo ed with no filtering element whatsoever wit in them, and thus serve solely as an oil cooling device. "'1

Although I have-shown in the accompanying drawings only one method of formingthe filter intoa compact unit, that is, b rolling it into a spiral formation, it wili e' apparent that this'may be varied as desired. For instance, the filter, as shown in Figs. 6 and 7 may be bent back and forth upon itself the exterior surface thereof.

of which is commensurate with the appended claims.-

What I claim is:

1. A filter comprising a ribbon-like filtering element enclosed in a ribbon-like sheet metal casing readily bendable about a line parallel to a face thereof and transverse to its length.

2. A filter comprising a relatively thin elongated imperforate sheet metal housin formed from a single strip of sheet metal an interiorly divided along its length by a filtering element.

3. A filter comprising a continuous relatively thin ribbon-like sheet metal housing bent about one or more lines transverse'to its length to form a relatively compact structure, a continuous relatively thin ribbon-like filtering element received in said'housing and sealed at its margins against the passage of liquid between said casing and said margins, and an inlet housing.

4. A filter comprising, in combination, a

ing, a filtering element received within said housing with its margins clainped between opposed walls of said housing, said housing between said margins being formed with a plurality of outwardly extending projections thereon, and an inlet and outlet for said housing.

5. A filter comprising, in combination, a ribbon-like filtering element, a housing for said filterin element comprising a str p of sheet metal ent upon itself between its margins and receiving said filtering element therein, the margins of said strip being sealed together over said filtering element, and an inlet and outlet for said housing.

6. A strip-like filter including a ribbonlike sheet metal housing enclosing a ribbonlike filtering-element bent into a relatively compact structure with portions of the exterior surface thereof in spaced but adjacent relationship with respect to other portions o 7. A ribbon-like filter including a ribbonlike sheet metal housing enclosing a ribbon- 'like filtering element formedinto a coiled structure, each .coil of which is generally spaced from the adjacent coil to permit the passage of cooling fluid between the same 8. A filter comprising a strip of filtering material encased in a housing and both of which are coiled, the various coils of said.

filter being'positioned relative to each other tolpermit the circulation of a cooling fluid between them.

and an outlet for said 9. A filter comprising, in combination, a strip of open mesh wire screen surrounded b a casing of filtering material, and all of whic is enclosed in a relatively thin ribbon-like sheet metal housing, said housing being interiorly divided over substantiall its entire length by said screen and materia and being ine between its margins, inserting a striplike filtering element between the opposed faces of saidbent strip, then bringmg to- 5 gether and sealing the margins of said strip about said element, and then coiling said strip and element.

12. The method of forming a filter comprising in pre aring a filtering element by enclosing a strip of screen by a sheetof filtering material, and then enclosing said screen and material by a sheet metal stri bent about a line between its margins and dim ing the margins of said stri and material tween opposed faces thereo 13. In combination with the lubricant circulation system of an internal combustion engine, a device form'infg'a part of said s stem com rising an imper crate sheet metal ousing ent into a spiral formation, said housing being provided with a plurality of lubricant conducting ribs extending in one direction to provide lubricant ducts, and a plurality of ribs extending in a direction at an angleto the first mentioned ribs, whereby said housing may be bent into spiral formation.

14. A filter comprising -a continuous ribbon-like sheet metal housing bent into a comact structure, a continuous ribbon-like filtermg element secured between 0' site side edges of said housing and divi mg the intenor thereof into two passages, an inlet for one of said passages .at one end of said ho'us ing, 'an outlet for the other of said passages at the other end of said housing, outwardly extending series of ribs formed on the exteriorof said housing and extending in the direction of the length thereof, andan outwardly extending transversely disposed rib formed on said housing between each of said series. 15. A filter comprising a filter element, a housing enclosing the fi-tering element, an inlet and an outlet in said housing on opposite sides and at opposite ends of said filtering element, longitudinal corrugations in said 11. The method of forming a filter comrising in bending a strip of metal about a housing spacing-the filtering element in the hous ng, said corrugations on the inlet side grovidlng a passage for the fluid to be ltered, said corrugations on the outlet side providing a passage for the filtrate, and transverse corrugatlons in-the housing. 4

g 16. A filter comprising a filter element, a convolute housing enclosing the filtering element, an inlet and an outlet in said housing on opposite sides and at op osite ends of said filterin element, longitu in'al corru ations in said ousing spacing the filtering e ement in the housing, said corrugations on the inlet slde providing a passage for the fluid to be filtered, said corrugations on the outlet side providing a passage for the filtrate, and

transverse corrugations in the housing, the convolutions of the housing being spaced by the transverse corrugations.

17. In combination with the lubricant circulation system of a machine, a cooling medium, a cooling device in said medium, said cooling device-forming a part of said system, compr sing a lubricant conducting housing, bent into convolutions and corrugatedlong1- tudinally and transversel the longitudinal corrugations forming lu ricant circulation ducts and the transverse corru ations spac-' ing the convolutions of the housing, whereby transverse passages are rovided for the cool ing medium between t e adjacent convolutions of thelubricant conducting housing.

18. In combination with the lubricantcirculation system of a machine, a cooling medium, a cooling device in said medium, said cooling device forming a part of said system, comprising a lubricant conducting housing, bent into convolutions and corrugated l0ng1- tudinally and transversel the longitudinal corrugations forming 'lu ricant circulation ducts and the transverse corrugations spacing the convolutions of the housing, correbent about one or more lines transverse to its length to form. a relatively .compact structure, a continuous relatively thin ribbon-like filtering element received in said housing and sealed at its margins against the passage of liquid between said casing and said margins, and an inlet and an outlet for said housing,

said inlet and outlet being on opposite sides of said filtering element, the sides of said strip having longitudinal corrugations therein, the inner portions of the corrugations spacing the strip intermediately of the housing and the outer portions of the corrugations forming ducts, for the fluid to be filtered sponding portions of the longitudinal cor- 6 -1 -,':'oo,oee-

on the inlet side, and for the filtrate on the outlet side;

20. A'filter comprising, in combination a ribbon-like filtering element a housing for 5 said filtering element com rising a'stri'p of sheet metal bent upon itsel between its margins and receiving said filtering element therein, the margins of said strip being sealed together over said filtering element, andan inlet and outlet for. said housing said inlet and outlet being on opposite sides of said filtering element, the sides of said strip having longitudinal corrugations therein, the inner portions of the corrugations spacin the strip intermediatel of the housing an the outer portion of t e corrugations formin the fluid to be filtered on the inlet side, an for the filtrate on the outlet side.

so SUMNER WILTSE. 

